Posted
by
kdawson
on Tuesday January 16, 2007 @09:44PM
from the no-more-go-boom dept.

Iddo Genuth writes "Conventional Li-Ion batteries have been known to catchfire and explode. A new, safer type of Li-Ion nanobattery that might help prevent such mishaps has been developed by researchers at Tel Aviv University. These nanobatteries should prove useful for various micro devices used for medical, military, and a range of other applications. They are 2-4 years from commercial availability."

Is there really that much of an explosion/fire risk for very small and microbatteries? Sure, these nanobatteries would be fantastic for small robots, but I'd guess we're well over 4 years away from being able to make large batteries (e.g. laptop batteries) utilizing nanofabrication techniques that could also reduce fire/explosion risks.

I would have thought that a correct use of the prefix 'nano' would involve an object, device or effect, the WHOLE of which is on a nanometre scale. So for example, a 'nanobattery' would be a battery the WHOLE of which is on a nanometre scale.

I'm obviously not alone is being heartily sick of anything involving components parts which are on an atomic scale (e.g.... uh, CHEMICALS) being referred to as 'nano'-whatever. For instance a while back we had this [slashdot.org] idiotic story about 'lead compounds' producing 'nanocrystals' and being used by the ancient Egyptians.

Next on slashdot: scientists develop nanobreathing technology using a nanogas mixture containing nanoparticles only an few atoms wide! Revolutionary nanopower technique delivers charged nanoparticles to electrical devices through ordinary wire! Nanolightbulbs emitting nanophotons found to have been in use since the 18th century! Nanocar constructed entirely from nanoparticles of metal, plastic and glass runs entirely on nano-fuel only a few carbon atoms long!

Since each nanobattery is comprised of thousands of small batteries, even if one of these small batteries has a short circuit and fails, the entire battery can keep functioning, lossing only a very small amount of power. Similar damage to a conventional Li-Ion battery could result in substantial loss of power or a complete malfunction and in extreme cases even fire or explosion.

So they're putting microcells in a series/parallel network, and claiming that, since each microcell contains minute quantities of energy, a short circuit would result in only minute consequences.

But, again, they've put the batteries in a series/parallel network. They don't mention that a short could take place in places in the network other than exactly across one cell. Let's say an impurity spec lands across a couple wires. Depending on which couple wires, you might have shorted just a few microcells, or you could be shorting out the whole battery.

The reason Li-Ion batteries are dangerous is the sheer energy density. Rearranging that energy with a different battery structure isn't going to negate the fact that, simplistically, you somewhere have two conductors across which is the entire potential of the battery. (Unless you divide the battery into segments and give each segment a unique load. However, that would require a fundamental re-thinking of how electronic devices are powered.)